A traditional mail delivery system involves physical sorting and sequencing of mixed mail, from collection of mail items until delivery to addresses printed on the items. To permit a machine to group and sequence mail items, addresses on the mail items must be interpretable to the level that permits correct sorting decisions. For delivery, the address on a mail item must be related to a delivery location, such as a post box or a location on a street. In both cases, up-to-date knowledge of addresses is required in order to correctly interpret and retrieve operational relationships.
In Canada, for example, there are over 11 million civic addresses in urban cities, plus over 3 million rural addresses which may only have personal names or business names associated with a route number and a township. Rural mail that has no urbanized addresses can only be sorted to the delivery route level. Beyond the route level, delivery is by addressee names based on personal knowledge of local delivery agents.
For many years, urban and rural addresses have been managed through bottom-up processes. The change management process is labor intensive, characterized by long latency, human errors, and significant costs to acquire and correct delivery addresses. Local delivery agents are relied upon to report and to visually validate changes. New addresses in newly developed areas are acquired through submissions by municipalities and real estate developers. After lengthy validation, changes are mapped onto business and operational attributes. A mapping process involves associating an address with data attributes. In Canada, an address would first be associated with a postal code which, if it is a new one, is added to mail processing sort plans, followed by association of the low level address with a delivery route number, a walk sequence number and time values, a mail box number and any special services such as redirection mail and hold mail that may also require association of individual names to addresses, etc. An address may be operationally “undeliverable” without a correct prior association. Address databases and operational directories of sort equipment are subsequently updated. Address changes are also acquired or cross validated with third party address databases. Data quality clearly depends on geographic coverage, completeness, currency, accuracy, and usefulness of the mapped-over business attributes.
Some mail sort equipment sorts to delivery routes by reading up to the street number in the destination address of each mail item to enable a sort decision. In Canada, the highly structured Canadian postal code of FSA LDU (Forward Sort Area Local Delivery Unit) also provides complete redundant information to permit sorting to delivery routes. Individual carriers subsequently use a sort case to manually order the pieces to line-of-route delivery sequence. Any addressing deviations, errors, and changes are handled by individual carriers based on personal knowledge and familiarity with their delivery areas.
Mechanical sequencing of mail to line-of-route delivery is also possible. Some systems sequence mail to outside street addresses only, for example. Other systems may also sequence inside unit numbers to further improve efficiency. However, the business process of address maintenance, data accuracy and error handling, attribute mapping, and change latency are non-trivial and are usually specific to the service environments. They become critical when human knowledge and in-situ decisions of local delivery carriers are replaced by machines.
To fully sequence mail, a machine needs to read and correctly interpret the last address attribute which, in the case of Canadian addresses, is apartment unit numbers in urban areas, personal names and business names in rural areas, as well as box numbers in certain delivery addresses. The present Canadian postal code does not provide sufficient redundant information to map onto a single dwelling unit. If the full mailing address is not also encoded in a barcode by a mailer, then there is no redundant information on a mail item to permit reliable optical reading and interpretation of the written address. Optically read addresses must first be parsed reliably to identify street name, street number, apartment unit number, box number, personal name, and business name. Because the presentation orders and formats of these low level attributes are inconsistent, a reference address directory is usually used to minimize uncertainties. Ideally, the reference directory should be a full set of attributes at any given time such that all valid live observations are always inclusively a subset of those attributes. Any shortcomings would increase parsing errors or delivery failures, as there is no other information to determine validity. Furthermore, in a deterministic sort system, a mail item is usually rejected from the line if an observed address has not been pre-mapped to a route or a sequencing order in a running sort plan.
Although mail is supposed to be delivered to a person or a business per address, in practice mail is delivered to a mail box or other destination where the person or the business is supposed to be located according to the address on a mail item. Addressee names, particularly personal names, are usually not known to the mail system, and for all practical purposes other than in the case of premium secure registered mail and redirected mail services for instance, names are not an operational attribute in urban delivery. This is not true in rural delivery where civic addresses might not exist. Personal names and business names are still the only way to differentiate delivery points. However, system complexity, scalability, and cost significantly increase where delivery service progresses from an address to an addressee, and ultimately to the addressed individual. In hybrid delivery services which are interactive and multi-media by nature, privacy protection and security require proper distinction and verifiable associations of addresses, addressee names, and the addressed individuals.
Mail sort plan and delivery route configurations are generally static, based on geographic features and delivery workload. Configuration changes are adjusted periodically when warranted by appreciable volumetric, demographic, or geographic changes. Because the change process is largely manual, cost, natural latency, and lack of reliable real-time data have confined change management to long term adjustments using volumetric averaging, timeline averaging, and geographic spatial averaging. Given the seasonal and cyclic nature of mail services, and the increasing traffic and volumetric gaps between residential homes and businesses, higher system efficiency requires higher proximity of system configurations to actual load demands in lieu of averaging that leverages workloads rather than efficiency.
For many years, delivery systems have been deterministic and addresses are treated as 100% accurate until proven otherwise. Increasingly, some business applications such as financial transactions, government services, and advertising campaigns desire prior knowledge of the quality of the addresses and occupancies before mailing for better mailing security and cost effectiveness management.
Conventional mail systems also typically collect only certain types of data from physical mail items to enable routing of those items, and store the collected data for only a relatively short amount of time. Actual usage of the collected data is thus significantly limited.